Raman Scattering Modification Induced by Structural Change in Alumina Polymorphs

The calculated Raman spectra disclose that alumina polymorphs of nordstrandite, gibbsite, diaspore, boehmite, bayerite and α-Al₂O₃ display different phonon behaviors, which can be attributed to their internal crystal structure changes. The strongest Raman peaks of nordstrandite, gibbsite, diaspore, boehmite, bayerite and α-Al₂O₃ are located at 214.2 cm^?1, 3314.4 cm^?1, 2298.6 cm^?1, 747.7 cm^?1, 3484.6 cm^?1 and 529.2 cm^?1, respectively. The characterizations in Raman spectra of those polymorphs are obviously different, which can be used in fingerprints to identify the alumina polymorphs structure.